Pentax S1a light seals

Nick Rowland · 10-20-2019, 07:54 AM

Hi All,

I am about to replace the light seals on my S1a and want to check where they are and the material to use, please.

I have found, two narrow foam seals in the top and bottom rear door channels, a felt seal by the door hinge, a felt seal by the door lock and one small thicker foam buffer pad hidden away on one side at the top of the mirror box. Have I missed any?

Does anyone know the foam type and thickness I should be using? I'm guessing 1.5mm closed cell for the channel seals and maybe 3mm for the buffer pad but I'm not sure.

Thanks in advance

Nick

**ismaelg** · 10-20-2019, 08:02 AM

Hello,

That's about it. I recently used foamie for sealing another camera but it turned out to be too thick. It was very hard to close and it was putting excessive pressure to the latch. I ended up using strips of black felt with very little to no adhesive as the pressure keeps it in place.

Thanks,
Ismael

**aslyfox** · 10-20-2019, 09:15 AM

are you using JIS screw drivers

it might be wise to look at this thread

Cross-head screws - a caution: - PentaxForums.com

Nick Rowland · 10-20-2019, 09:20 AM

Originally posted by ismaelg

Hello,

That's about it. I recently used foamie for sealing another camera but it turned out to be too thick. It was very hard to close and it was putting excessive pressure to the latch. I ended up using strips of black felt with very little to no adhesive as the pressure keeps it in place.

Thanks,
Ismael

Ok thanks, I want to replace like with like. I'm just not sure if I should use 1mm or 1.5mm foam for the back. I won't replace the felt seals unless I need to but I do have velvet I use for Large Format film holders, which is about the same

---------- Post added 10-20-19 at 09:21 AM ----------

Originally posted by aslyfox

are you using JIS screw drivers

it might be wise to look at this thread

Cross-head screws - a caution: - PentaxForums.com

Yes, I have a set of JIS but I shouldn't need to dismantle anything as far as I can see, have I missed something?

**ismaelg** · 10-20-2019, 09:29 AM

Originally posted by Nick Rowland

Yes, I have a set of JIS but I shouldn't need to dismantle anything as far as I can see, have I missed something?

Not for the light seals as far as I know.

**aslyfox** · 10-20-2019, 09:47 AM

Originally posted by Nick Rowland

. . . Yes, I have a set of JIS but I shouldn't need to dismantle anything as far as I can see, have I missed something?

I don't know

I know my limitations and working on lenses is beyond me

good luck

**boriscleto** · 10-20-2019, 09:49 AM

Originally posted by aslyfox

I don't know

I know my limitations and working on lenses is beyond me

good luck

Why would you need to dismantle a lens to replace the light seals on the film door?

**arnold** · 10-20-2019, 09:55 AM

I'm not sure, but I thought the S series was before they started using foam seals. I have cameras that don't need seals due to the way they were designed. As mentioned, I'm not sure.

**aslyfox** · 10-20-2019, 09:57 AM

the OP was talking about working on the camera my post was more general in nature about what might next be done than what the OP is doing right now

**pentageek** · 10-20-2019, 10:31 AM

You may take a look at this light seals kit. There is also pre-cut variant of light seal foam. I've used a set from this manufacturer, and everything worked well.

Nick Rowland · 10-20-2019, 10:37 AM

Originally posted by arnold

I'm not sure, but I thought the S series was before they started using foam seals. I have cameras that don't need seals due to the way they were designed. As mentioned, I'm not sure.

There is hardened foam for sure in the door grooves and the mirror damper is definitely foam.

---------- Post added 10-20-19 at 10:38 AM ----------

Originally posted by pentageek

You may take a look at this light seals kit. There is also pre-cut variant of light seal foam. I've used a set from this manufacturer, and everything worked well.

Ooh thanks, I do have the foam sheets but find cutting it a challenge, so that pre-cut stuff is right up my street :-)

stevebrot · 10-20-2019, 12:50 PM

Originally posted by Nick Rowland

Yes, I have a set of JIS but I shouldn't need to dismantle anything as far as I can see, have I missed something?

You should not have to dismantle and even if you did, the S1a does not have cross-head screws. That came later.

As for seals, Jon Goodman has the best kits. The question might be whether he has one for the S1a.

Steve

stevebrot · 10-20-2019, 01:15 PM

Originally posted by arnold

I'm not sure, but I thought the S series was before they started using foam seals. I have cameras that don't need seals due to the way they were designed. As mentioned, I'm not sure.

The S-series was essentially modern in construction with almost all models released in the early 1960s and some continuing into the late 1960s (1968 for the SV and S1a). They do employ light seals for the film door grooves and hinge plate. You bring up a good point though in regards to replacement. It is important to check whether there are existing seals and whether they are bad.* For example, the hinge seal is cloth and usually does not require replacement. The door grooves may have been done with doped twine at some point, in which case they are practically immortal.

Steve

(...my SV was CLA'd by Eric and he used doped twine...)

* By way of comparison, my late 1950s vintage Canon P does NOT use seal material in the film door light traps.

Nick Rowland · 10-20-2019, 02:12 PM

Originally posted by stevebrot

As for seals, Jon Goodman has the best kits. The question might be whether he has one for the S1a.
Steve

I did look for him but he seems to have disappeared around 2017, nothing on the web and his Ebay shop has nothing for sale.

I can probably make some, in theory they are just simple strips but I never get the thin ones quite right.

I'm still trying to double check the foam height and width dimensions but just can't find it mentioned anywhere.

stevebrot · 10-20-2019, 02:40 PM

Originally posted by Nick Rowland

I did look for him but he seems to have disappeared around 2017, nothing on the web and his Ebay shop has nothing for sale.

Jon quit his interslice eBay store several years ago and deals exclusively through email now. His address is jgood21967@aol.com. My understanding is that he has a representative in Britain who handles sales of kits and seal materials there and for the EU. He is also a PF member and may be contacted by private message here as well.

Jon Goodman - View Profile - PentaxForums.com ( @Jon_Goodman )

Steve

10-20-2019, 07:54 AM	#1
Nick Rowland Junior Member Join Date: Oct 2019 Location: Eastbourne, Sussex, UK Posts: 36	Pentax S1a light seals Hi All, I am about to replace the light seals on my S1a and want to check where they are and the material to use, please. I have found, two narrow foam seals in the top and bottom rear door channels, a felt seal by the door hinge, a felt seal by the door lock and one small thicker foam buffer pad hidden away on one side at the top of the mirror box. Have I missed any? Does anyone know the foam type and thickness I should be using? I'm guessing 1.5mm closed cell for the channel seals and maybe 3mm for the buffer pad but I'm not sure. Thanks in advance Nick

10-20-2019, 01:15 PM	#13
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by arnold I'm not sure, but I thought the S series was before they started using foam seals. I have cameras that don't need seals due to the way they were designed. As mentioned, I'm not sure. The S-series was essentially modern in construction with almost all models released in the early 1960s and some continuing into the late 1960s (1968 for the SV and S1a). They do employ light seals for the film door grooves and hinge plate. You bring up a good point though in regards to replacement. It is important to check whether there are existing seals and whether they are bad.* For example, the hinge seal is cloth and usually does not require replacement. The door grooves may have been done with doped twine at some point, in which case they are practically immortal. Steve (...my SV was CLA'd by Eric and he used doped twine...) * By way of comparison, my late 1950s vintage Canon P does NOT use seal material in the film door light traps. Last edited by stevebrot; 10-20-2019 at 02:05 PM.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Spotmatic light seals in an SV	nickthetasmaniac	Film SLRs and Compact Film Cameras	6	06-03-2019 11:58 AM
Great news for those with intact light seals!	dsmithhfx	Film SLRs and Compact Film Cameras	7	01-02-2019 05:07 PM
Pentax 67 Light Seals	PhilRich	Pentax Medium Format	6	08-23-2018 06:24 PM
Pentax S1a to Repair or Buy	PenPusher	Film SLRs and Compact Film Cameras	16	05-18-2018 02:38 AM
S1A light meter help!	cameranewbie	Film SLRs and Compact Film Cameras	4	08-10-2014 03:13 PM

10-20-2019, 08:02 AM	#2
ismaelg Loyal Site Supporter Join Date: Apr 2009 Location: Puerto Rico Photos: Gallery Posts: 2,681	Hello, That's about it. I recently used foamie for sealing another camera but it turned out to be too thick. It was very hard to close and it was putting excessive pressure to the latch. I ended up using strips of black felt with very little to no adhesive as the pressure keeps it in place. Thanks, Ismael

10-20-2019, 09:15 AM	#3
aslyfox Seeker of Knowledge Join Date: Aug 2016 Location: Topeka, Kansas Photos: Gallery \| Albums Posts: 24,581	are you using JIS screw drivers it might be wise to look at this thread Cross-head screws - a caution: - PentaxForums.com

10-20-2019, 09:20 AM	#4
Nick Rowland Junior Member Join Date: Oct 2019 Location: Eastbourne, Sussex, UK Posts: 36 Original Poster	Originally posted by ismaelg Hello, That's about it. I recently used foamie for sealing another camera but it turned out to be too thick. It was very hard to close and it was putting excessive pressure to the latch. I ended up using strips of black felt with very little to no adhesive as the pressure keeps it in place. Thanks, Ismael Ok thanks, I want to replace like with like. I'm just not sure if I should use 1mm or 1.5mm foam for the back. I won't replace the felt seals unless I need to but I do have velvet I use for Large Format film holders, which is about the same ---------- Post added 10-20-19 at 09:21 AM ---------- Originally posted by aslyfox are you using JIS screw drivers it might be wise to look at this thread Cross-head screws - a caution: - PentaxForums.com Yes, I have a set of JIS but I shouldn't need to dismantle anything as far as I can see, have I missed something?

10-20-2019, 09:29 AM	#5
ismaelg Loyal Site Supporter Join Date: Apr 2009 Location: Puerto Rico Photos: Gallery Posts: 2,681	Originally posted by Nick Rowland Yes, I have a set of JIS but I shouldn't need to dismantle anything as far as I can see, have I missed something? Not for the light seals as far as I know.

10-20-2019, 09:47 AM	#6
aslyfox Seeker of Knowledge Join Date: Aug 2016 Location: Topeka, Kansas Photos: Gallery \| Albums Posts: 24,581	Originally posted by Nick Rowland . . . Yes, I have a set of JIS but I shouldn't need to dismantle anything as far as I can see, have I missed something? I don't know I know my limitations and working on lenses is beyond me good luck

10-20-2019, 09:49 AM	#7
boriscleto Loyal Site Supporter Join Date: Dec 2009 Location: North Syracuse, NY Photos: Gallery Posts: 16,475	Originally posted by aslyfox I don't know I know my limitations and working on lenses is beyond me good luck Why would you need to dismantle a lens to replace the light seals on the film door?

10-20-2019, 09:55 AM	#8
arnold Site Supporter Join Date: Aug 2012 Location: Queensland Photos: Gallery \| Albums Posts: 4,294	I'm not sure, but I thought the S series was before they started using foam seals. I have cameras that don't need seals due to the way they were designed. As mentioned, I'm not sure.

10-20-2019, 09:57 AM	#9
aslyfox Seeker of Knowledge Join Date: Aug 2016 Location: Topeka, Kansas Photos: Gallery \| Albums Posts: 24,581	the OP was talking about working on the camera my post was more general in nature about what might next be done than what the OP is doing right now

10-20-2019, 10:31 AM	#10
pentageek Site Supporter Join Date: Jan 2016 Posts: 420	You may take a look at this light seals kit. There is also pre-cut variant of light seal foam. I've used a set from this manufacturer, and everything worked well.

10-20-2019, 10:37 AM	#11
Nick Rowland Junior Member Join Date: Oct 2019 Location: Eastbourne, Sussex, UK Posts: 36 Original Poster	Originally posted by arnold I'm not sure, but I thought the S series was before they started using foam seals. I have cameras that don't need seals due to the way they were designed. As mentioned, I'm not sure. There is hardened foam for sure in the door grooves and the mirror damper is definitely foam. ---------- Post added 10-20-19 at 10:38 AM ---------- Originally posted by pentageek You may take a look at this light seals kit. There is also pre-cut variant of light seal foam. I've used a set from this manufacturer, and everything worked well. Ooh thanks, I do have the foam sheets but find cutting it a challenge, so that pre-cut stuff is right up my street :-)

10-20-2019, 12:50 PM	#12
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by Nick Rowland Yes, I have a set of JIS but I shouldn't need to dismantle anything as far as I can see, have I missed something? You should not have to dismantle and even if you did, the S1a does not have cross-head screws. That came later. As for seals, Jon Goodman has the best kits. The question might be whether he has one for the S1a. Steve

10-20-2019, 02:12 PM	#14
Nick Rowland Junior Member Join Date: Oct 2019 Location: Eastbourne, Sussex, UK Posts: 36 Original Poster	Originally posted by stevebrot As for seals, Jon Goodman has the best kits. The question might be whether he has one for the S1a. Steve I did look for him but he seems to have disappeared around 2017, nothing on the web and his Ebay shop has nothing for sale. I can probably make some, in theory they are just simple strips but I never get the thin ones quite right. I'm still trying to double check the foam height and width dimensions but just can't find it mentioned anywhere.

10-20-2019, 02:40 PM	#15
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by Nick Rowland I did look for him but he seems to have disappeared around 2017, nothing on the web and his Ebay shop has nothing for sale. Jon quit his interslice eBay store several years ago and deals exclusively through email now. His address is jgood21967@aol.com. My understanding is that he has a representative in Britain who handles sales of kits and seal materials there and for the EU. He is also a PF member and may be contacted by private message here as well. Jon Goodman - View Profile - PentaxForums.com ( @Jon_Goodman ) Steve